The Campaign to Protect Rural England (CPRE) has identified the best and worst performing councils in allowing new homes to be built on previously developed brownfield land.

But Corby, which has been labelled the worst council, say this is unfair because it has built housing on former quarries which is not counted because of a glitch with the classification system.

Brownfield is a loose term used to describe land which has already been developed, as opposed to green field sites, which have not.

David Lock, chairman of the Town and Country Planning Association, believes there has been confusion over the term, from when it was originally devised and following a change in planning legislation.

When the last official version of the planning legislation was introduced in 2000, the government introduced the phrase 'previously developed land' (PDL) under its Planning Policy Guidance, note three.

The peak district national park... has quarries in it and if they were assumed to be brownfield sites, ripe for development, it would be absurd and very damaging

PDL excluded land which had been quarried, mined or in some way damaged, but which had been subject to a restoration condition.

This is where permission has been granted to quarry land on the condition that afterwards it is turned into forest or agricultural land.

Mr Lock believes when people now talk about brownfield, they are using the old term.

He said: "Corby built homes on a former quarry, but because it was subject to a restoration condition, it was not classified as PDL and so not included as a brownfield site.

"This has caused confusion, whereas the previous definition of brownfield was more broad and so easier to understand."

But the CPRE feels there is no confusion and it is unnecessary to change the classification of quarries.

CPRE head of planning Henry Oliver said: "The official definition of brownfield quite clearly excludes restored mineral lands and as a general rule the CPRE thinks that is right.

"The peak district national park, for example, has quarries in it and if they were assumed to be brownfield sites, ripe for development, it would be absurd and very damaging."

Residential gardens

Residential gardens also qualify as brownfield sites and some councils concede they have been used for development when land is limited.

But the government says this does not mean that gardens are up for grabs by developers as there are sufficient laws to protect against this.

A spokesman for the Department for Communities and Local Government said: "Of course it is the case that when old housing in our towns and cities needs replacing that developers build on residential land where the old housing stood.

"But local authorities have plenty of powers to protect gardens if proposed development is inappropriate.

"New homes have to be built somewhere and we make no apology for prioritising suitable brownfield sites to increase the protection of the countryside."

Mr Oliver said: "There is a case for some intensification in urban and suburban areas to make them more sustainable, and sometimes that will mean building on gardens.

"However, [the] CPRE thinks it is very important that the process should be much more tightly controlled by councils and focused on places where it does least harm to the local community."